LESSON 2: ISOTHERMS
Will it be warm outside tomorrow?Certain weather maps allow us to view warm and cold areas in an easy
fashion. One helpful weather map contains isotherms. An isotherm is a line
connecting locations with equal temperature. Isotherm
maps show where temperatures are relatively high and low, and also where
temperature changes are gradual or dramatic over a distance.
This image shows an example of a weather map containing 60° and 70°
isotherms. The large black lines are called isotherms. They are typically placed
at intervals of 10 degrees Fahrenheit.
2 and print out the map with temperature readings.
- This activity will assist you in creating and interpreting weather maps
1. Determine which
10 degree intervals will be necessary to use for this map.
2. Draw in the
isotherms on the map you have printed out. Label each isotherm.
can be used to identify air masses (large areas of the lower atmosphere with
similar weather). Air masses are generally referred to as cold or warm. Cold air
masses are colder in the center, and warm air masses are warmer in the
3. Name a state over which a cold air mass is located?
a state over which a warm air mass is located?
Air masses are also
categorized as dry or humid. Humid air masses develop over ocean waters. Dry air
masses come from large land areas. An air mass found over the Gulf of Mexico
would be humid and warm. An air mass located in central Canada in winter would
be dry and cold.
5. How would you describe the air mass moving into the
United States from Canada?
- Maps from The Weather
- Maps from Tiger Census Maps
Written by: Gene Rempel and Mike
Last Modified September 19, 1998